Hydraulic transmission mechanism



J. BEDFORD.

HYDRAULIC TRANSMISSION HECHANISI Filed Oct. 5,1951

18 Sheets-Sheet l Aug. 22., 1933.-- J. BEDFORD HYDRAULIC TRANSMISSION MECHANISM Filed Oct. 5, 1931 18- Sheets-Sheet 2 Aug. 22, 1933.

J BEDFORD HYDRAULIC TRANSl lISSION IECHANISI Filed Oct. 5, 1931 1a- Sheets-Sheet s Aug. 22 1933. J. BEDFORD v 1,924,0l7

HYDRAULIC TRANSMISSION MECHANISM Filed Oct. 5, 1931 18 Sheets-Sheet 4 Aug. 22, 1933. J. BEDFORD 1,924,017

HYDRAULIC TRANSMISSION MECHANISM Fil ed Oct. 5, 1931 18 Sheets-Sheet 5 I J ed Fc/LaL Aug. 22, 1933.

J. BEDFORD HYDRAULIC TRANSMISSION MECHAN IS K 18 Sheets-Sheet 6 Filed Oct. 5, 1931 l l 'row- 1 -Au .,,22, 1933. J. BEDFORD 1,924,017

HYDRAULIC TRANSMISSION MECHANISM Filed Oct. 5, 1931 18 Sheets-Sheet 7 Aug 22, 1933. J. BEDFORD 1,924,017

HYDRAULIC TRANS-MISSION r aracnm xsu Filed Oct. 5, 1951 18 Sheets-Sheet'8 Aug. 22, 1933. J. BEDFORD I 1,924,017 HYDRAULIC TRANSMISSION uncl-mmsm Filed 001;. 5, 1931 18 Sheets-Sheet 9 Aug. 22, 1933. BEDFbRD I 1,924,017

HYDRAULIC TRANSMISSION MECHANISM Filed Oct. 5, 1931 18 Sheets-Sheet 10 .171 I 175 mm J Bap/wt I v Aug. 22, 1933. J. BEDFORD 1,924,017

HYDRAULIC TRANSMISSION MECHANISM Filed Oct. 5, 1931 1a Sheets-Sheet 11 f U- J J/e (11 2 BY W7 M5 1 .1

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HYDRAULI C TRANSMI S 5 10M MECHANISI FiledOct. 5, 1931 l8 Sheets-Sheet 12' J Belf MY 73 R Aug. 22, 1933. J. BEDFQRD 1;924,p17

' HYDRAULIC TRANSMISSION iJEiEHANISM Filed Oct. 5, 1931 A 18 Sheets-Shelf. 13

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HYDRAULIC TRANSMISSION MECHANI SM Filed Oct. 5, 1931 18 Sheets-Sheet 14 Aug, 22, 1933. J BEDFORD 1,924,017

HYDRAULIC TRANSMIS S ION MECHANISM .Filed 001;. 5, 1931 18 Sheets-Sheet 15 Aug. '22, 1933. Y EDFORD 1,924,017

HYDRAULIC TRANSMISSION MECHANISM Filed 001:. 5, 1951 18 Sheets-Sheet 1s 1933 J BEDFORD 1,924,017 I. I HYDRAULI C TRANSMIS S ION MEEHANISM Fiied Oct. 5, 1931 18 Sheets-Sheet 17 Federated Aug. 22, 193

BAULIG FRANSRHSSION MECHANISM Jesse Redford, Luton, England, assigno'r of onehalf, England to 'Matthew Clough. Park, Luton,

Application October 5, 1931, Serial No. 567,092,

' and in Great Brit Qctoher 6, 19343 a clai (or. 60-53) l'his invention relates to improvements in hydraulic transmission mechanism such as that for transmitting motion from one shaft to another at any desired speed and in any desired direction.

It is an object of the present invention to simplify such mechanism and at the same time to eliminate friction gearing, gear wheels and chains and to reduce friction to a minimum.

A further object of the invention is to provide mechanism of the above kind which, willgive a smooth and infinitely variable effect and at the same time provide in one mechanism the iunctions of a clutch and a change-speed gear whilst eliminating the undesirable features of such mechanism.

A further "object of the invention is to reduce relative motion between the working parts of such mechanism to a minimum and at the same time to so arrange the moving parts as to obtain dynamic and static balance whilst providing a uniform and balanced torque.

A still further object of the invention is to reduce the travel of the working fluid and the volume displaced to a minimum and thus utilize 2 the energyof the fluid in the shortest space and most eficient manner.

Other objects of the invention will be apparent from the description given hereinafter.

The invention accordingly comprises hydraulic transmission mechanism embodying a variable delivery pump and a variable receiving pump or motor, said pumps being so arranged and adapted that as the capacityof the delivery pump is increased the capacity of the receiving pump or motor is decreased.

The invention also comprises hydraulic transmission mechanism according to the preceding paragraphs wherein the delivery pump comprises cylinders and means for reciprocating pistons therein and said cylinders and the means for reciprocating the pistons therein are rotatable.

The invention also comprises a gear according tothe above paragraphs arranged so that when the capacity of the motor is zero a direct drive is transmitted between thedrlving and following shafts.

Further features of the invention will be hereinafter indicated or described.

In the accompanying drawings:

Figure 1 is a sectional side elevation oi one form of gear in accordance with the invention taken on the line AA of Figure 2 Figure 2 is a partsectional end elevation of gear of which the portion E is a section taken on the line 3-3 of Figure l;

Figures 3, 4, 5 and 6 are partial sections of the gear taken respectively on the lines E-E, D-D, C-C and BB of Figure 1 showing the construction of valve mechanism for distributing the working fluid;

Figure 7 is a sectional side elevationof another form of gear in accordance with the invention taken on-the line F--F of Figure 8;

Figure 8 is a part sectional end elevation of the gear, of which the portions G, H represent sections takenmespectively on the lines G-G and H-H of Figure 7;

Figure 9 is a-sectionalview of part of thecontrol mechanism;

Figure 10'isa partial section taken on the line L-L of Figure 7 showing the arrangement of passages for theworking fluid;

Figures 11, 12, 13 and 14 are partial sections of the gear taken respectively on the lines J-J, K-K,' M--M, N-N of Figure '7 showing the arrangement of valve mechanism for the distribution of the working fluid;

- Figure 15 is a sectional side elevation of a further form of gear in accordance with the invention taken on the line P--P of Figure 16;

Figure 16 is a part sectional end elevation of the gear, of which the portions Q, R are sections taken respectively on the lines RR of Figure 15;

Figure 17 illustrates part of the control mechanism in position for direct forward drive;

Figure 18 illustrates the same part of the control mechanism in position for reverse drive;

Figure 19 is a sectional side elevation of still a further form of gear in accordance with the invention; I I

Figure 20 is a part sectional end elevation of the gear of whichthe upper half is a section taken on the line S--S of Figure 19 and the lower half is an end elevation of the mechanism with the rear cover plate and shaft removed;

Figure 21 is a sectional side elevation of still a further form of gear in accordance with the invention;

Figure 22 is a sectional end elevation oi the gear taken on the line. T-T of Figure 21 with the tilting members thereof adjusted to the position or zero tilt;'

Figure 23 illustrates part oi the control mechanism;

Figures 2a and 25 are part'sectional plans other parts of the control mechanism;

Figure 26 is a sectional side elevation of still a further form of gear in accordance with the invention;

Figure 27 is a part sectional end elevation of the gear of which the upper half is a section taken on the line U-U of Figure 26 and the lower half is a partial end view of the mechanism with the rear cover plate removed;

Figure 28 is a sectional plan of part of the control mechanism;

Figure 29 is a sectional side elevation of still a further form of gear in accordance with the invention taken on the line VV of Figure 30;

Figure 30 is a sectional end elevation of the gear taken on the line W-W of Figure 29;

Figures 31, 32 and 33 are partial sections of the gear taken respectively on the lines XX, YY and ZZ of Figure 29 showing the arrangement of valve mechanism for distributing the working fluid;

Figure 34 is a sectional side elevation of still a further form of gear in accordance with the invention taken on the line A-A' of Figure 35;

Figure 35 is a sectional end elevation of the gear taken on the line B-B of Figure 34;

Figure 36 is an elevation of a part of the control mechanism;

Figure 37 is a sectional plan of another part of the control mechanism; Figure 38 is a partial section taken on the line C-C of Figure 34 showing the arrangement of part of the valve mechanism used for distributing the working fluid;

Figure 39 is a partial section taken on the line D-D! of Figure 34 showing the arrangement of further valve mechanism for distributing the working fluid, and

Figure 40 is a diagrammatic arrangement of still a further form of gear in accordance with the invention. t

In the following description, like reference numerals are used throughout to represent like parts and in the drawings the driving and following shafts are indicated by the references 1 and 2 respectively and the casing of the gear by the reference 3.

In carrying the invention into effect in one convenient manner and as illustrated in Figures 1 to 6 a cylinder block 4, rigidly mounted on the following shaft 2, is provided with four radially disposed groups of cylinder bores 5, 6 5 6 in which corresponding pistons '7, 8 7 8 are arranged to be reciprocated by the action of eccentrically mounted circular rings 9, 10 9 10 with which they engage through ball bearing rollers 11 carried by pins 12 on extensions 13 of the said piston. The cylinders of each group lie in one plane and those in'the groups 5 are angularly staggered relatively to those in the groups 6 as indicated in Figure 2. The rings 9 10 are carried by a member 14 rigidly mounted on the driving shaft 1 and form with the cylinders 5 6 and the pistons 7 8 the pump element of the gear while the rings 9 10 which are carried by the casing 3 form with the cylinders 5 6 and the pistons 7 8 the motor element of the gear.

It is evident that relative rotation of the driving shaft 1 and the cylinder block 4 carried by the following shaft 2 will cause the eccentric rings 9, 10 to reciprocate the pistons 7, 8

. while similarly reciprocation of the pistons 7 8" will, through the medium of the eccentric rings 9", 10 cause rotation of the cylinder block 4 and with it the following shaft 2.

Keep rings 15 disposed internally of the rollers 11 and engaging therewith maintain them in contact with the said eccentric rings. The member 14 and the cylinder block 4 are mounted on extensions 16 and 17 formed respectively on the driving and following shafts 1 and 2.

Means are provided for varying the eccentricity of the said eccentric rings, that for the rings 9a, 10 which are slidably mounted in the member 14 comprising a pair of levers 18 pivoted at 19 on opposite sides of themember and formed with surfaces 20 to engage the two eccentric rings 9, 10 and interconnected by a member 21, being pivotably connected thereto at 22. A ring 23 arranged to be slidably moved along the extension 16 of the driving shaft 1 by operating levers 24 which, acting through pins 25 and a ball race 26, is connected at one side, as shown in the upper half of Figure 1, by a toggle link 27 to one side of the member 21, and, at the other side, as shown in the lower half of Figure l, by a similar toggle link 2'7, to one end of a lever 28 pivotably mounted at 29 on the member 21. The other end of the said lever 28 is pivotably connected to the adjacent ring operating lever 18 at its point of connection 22 with the member 21. The arrangement thus provided ensures that operation of the levers 24 will positively displace the-rings 9, 10 in opposite directions from their positions of zero eccentricity as shown in Figure 1 so that they take up positions of eccentricity on opposite sides of their axis of rotation. The position of the toggle links corresponding to maximum eccentricity of the rings is indicated by the chain dotted lines in Figure 1. Similarly, the rings 9", 10 are slidably mounted in the casing 3, but in this case the means for varying their eccentricity consists of a pair of spindles 30 journalled in the casing on opposite sides thereof and each carrying a pair of crank pins 31' each of which pins engages in a groove formed in one of the rings 9, 10 so that rotation of the spindles 30 will impart opposite eccentric displacements to the said rings. The means for operating the rings 9, 9 and the rings 10, 10 are so connected by levers 32, links 33 and levers 34, connected by a spindle 35 with the levers 24, that one set of rings, e.g. 9, 9 is initially in a position of zero eccentricity while the other set is in a position of maximum eccentricity. Operation of the control mechanism will thus impart-an eccentric displacement to one set of rings while progressivelyreducing that of the other set to zero.

The cylinder bores 5 (:7 are provided with non- 125 return suction and delivery valves 36, 37 communicating with corresponding suction and delivery chambers or passages 38, 39, which passages also communicate with the cylinder bores 5 6* through ports 40, 41 formed in the cylinder 130 block 4 and under the control of a rotary valve 43. This valve is formed with ports 44, 45 to correspond with the ports 40, 41 and is rotated at half the speed of the following shaft by an epicyclic train comprising a pair of planet pinions 135 46, 47 keyed together and journalled on a pin 48; carried on the cylinder block 4, one of which pinions 46 engages with teeth 49 formed on the said valve 43 while the other pinion 47 engages with teeth 50 formed on a member 51 carried by 140 the casing 3. The member 51 is arranged to be partially rotatable about a portion 52 of the casing by longitudinal movement of a rod 53 which engages with the said member through a pin 54 and slot 55. Angular displacement thus impart- .145 ed to the member 51 will be transmitted to the valve 43' and will have the effect of altering the relative timing of the ports 44, 45 in the valve and the ports 40, 41 in the cylinder block'4, by which means a reverse drive may 150 

